Toxicity of Some Plant Extracts and Entomopathogenic Nematode against Pomegranate Aphid, Aphis punicae under Laboratory Condition

Abstract

The in vitro aphicidal activity of five medicinal and aromatic plant extracts at concentrations of 10, 5 and 2%; and entomopathogenic nematode, Steinernema feltiae with levels of 2000, 1000, 500 and 250 IJs on the mortality of pomegranate aphid, Aphis punicae (Hemiptera: Aphididae) were evaluated after 12, 24, 48 and 72 hrs of exposure time. The plants used were Azadiracta indica, Calotropis procera, Catharanthus roseus, Withania somnifera and Tagetes erecta. Results revealed that individual mortality percentages generally increased with the increase of extract concentrations and nematode levels for every exposure times of four tests. Among treatments of the extracts, A. indica significantly gave the highest value (77.9%) for every concentrations and exposure times; followed by C. procera with value of 71.5%; whereas, treatment of C. roseus gave the lowest significant value of pomegranate aphid mortality that was amounted to be 23.4%. In respect to entomopathogenic nematode, 2000 IJs was the best level at all durations of exposure. On the other hand, level of 250 IJs gave the lowest mortality of A. punicae individuals after 24 and 48 h of exposure. The study indicates the possible use of such botanicals and S. feltiae as well against pomegranate aphid.